[clang] [clang][SYCL] Disable float128 device mode diagnostic (PR #128513)

[Nicolas Miller via cfe-commits]

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@@ -4700,7 +4700,8 @@ void Sema::AddModeAttr(Decl *D, const AttributeCommonInfo &CI,
 
   if (NewElemTy.isNull()) {
     // Only emit diagnostic on host for 128-bit mode attribute
-    if (!(DestWidth == 128 && getLangOpts().CUDAIsDevice))
+    if (!(DestWidth == 128 &&
+          (getLangOpts().CUDAIsDevice || getLangOpts().SYCLIsDevice)))
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npmiller wrote:

Side-note `CUDAIsDevice || SYCLIsDevice` seems like a pretty common pattern and I believe HIP also uses `CUDAIsDevice`, it could be good to refactor in the future this to have a common "device compilation" option if possible.

https://github.com/llvm/llvm-project/pull/128513